I'm in the process of trying to write a novel and I'm currently trying to refine some of the plot devices. I'm aware that gene therapy using viral vectors typically involves adenoviruses or retroviruses and I was wondering if influenza could be used in a similar way. If not could it be modified in a way that would make it more suitable for use in this way?

i think what you want is a vector that has DNA (or can generate DNA like retroviruses) that can be inserted into the genome of the host. Influenza does not do this, or nothing like it, so I don't think you could do it (I know, never say never, but I don't see how)

"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

For the purposes of the virus in my novel it needs to be highly contagious but with relatively mild effects (something like common cold or flu symptoms) and capable of integrating with the host's genome. It also needs to be neuroinvasive, non-lytic and antiviral resistant. Is there any strain of virus that would fill most or all of these criteria (I've looked at adeno-associated viruses as a potential candidate but I'm unsure if they could satisfy the contagious aspect)?

When I say neuroinvasive I mean that it selectively or preferentially infects neural tissue. The virus would be designed not to kill its host cell but rather to carry therapeutic genes and integrate with the genome hence it would have to be non-lytic. For the purposes of a plot device laws and restrictions don't apply as the characters responsible for the creation are unscrupulous and not constrained by such. The idea of common cold or flu-like symptoms would be for transmission and this may mean the virus would have to infect lung tissues as well but in a different manner than how it infects neural tissues. I am unsure if a virus can be engineered to affect tissue types differently.

@prometheus: what about herpes simplex? it doesn't integrate but it has dsDNA that can remain inside the nucleus of nerve cells for years. it is not inconceivable to have recombination effects between the viral and genomic DNA. herpes is kinda treatable: you can treat it with the antiviral acyclovir which inhibits its DNA polymerase, but that won't get rid of virus for sure. And one can always imagine mutations that would render the enzyme immune to acyclovir.

"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

@JackBean: Even though it's science-fiction I'm writing I like to put the emphasis on the 'science' making it as believable as possible by grounding it in real facts. I would like the virus to be based on an existing strain.

@MrMistery: I'll look into herpes simplex. I believe it is already used as a viral vector in gene therapy and can target neural tissue.

@mith: The novel will be set in the near-future (1-2 decades). I'm not sure how far nanotechnology will have progressed but I have no doubt it would be possible to engineer a vector using such technology. However as stated I would like it to be an existing virus.